Fair Value Measurements (Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended
May 31, 2020	Feb. 28, 2021	Feb. 29, 2020
Percentage of marketable securities investments mature within one year		65.00%
Percentage of marketable securities investments mature within one to three years		35.00%
Fair Value, Measurements, Nonrecurring [Member]
Assets fair value adjustments		$ 0	$ 0
Liabilities fair value adjustments		$ 0	$ 0
Net Irrigate, LLC [Member]
Earn-out liability payment period	1 year
Maximum potential payout	$ 1,500,000

Business combination contingent consideration maximum potential earnout payment.

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Business combination earn-out liability payment period.

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Percentage of marketable securities investments mature within one to three years.

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Percentage of marketable securities investments mature within one year.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

No definition available.

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Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

No definition available.

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